Human nature is imperfect.

Human nature is evil; its goodness derives from conscious activity. Now it is human nature to be born with a fondness for profit. Indulging this leads to contention and strife, and the sense of modesty and yielding with which one was born disappears. One is born with feelings of envy and hate, and, by indulging these, one is led into banditry and theft, so that the sense of loyalty and good faith with which he was born disappears. One is born with the desires of the ears and eyes and with a fondness for beautiful sights and sounds, and, by indulging these, one is led to licentiousness and chaos, so that the sense of ritual, rightness, refinement, and principle with which one was born is lost. Hence, following human nature and indulging human emotions will inevitably lead to contention and strife, causing one to rebel against one’s proper duty, reduce principle to chaos, and revert to violence. Therefore one must be transformed by the example of a teacher and guided by the way of ritual and rightness before one will attain modesty and yielding, accord with refinement and ritual, and return to order.

Human nature is said by many to be good; if so, where have social evils come from? For human nature is the only moral nature in that corrupting thing called "society." Every example set before the child of to-day is the fruit of human nature. It has been planted on every possible field — among the snows that never melt; in temperate regions, and under the line; in crowded cities, in lonely forests; in ancient seats of civilization, in new colonies; and in all these fields it has, without once failing, brought forth a crop of sins and troubles.

Human nature is evil, and goodness is caused by intentional activity.

Human nature is not nearly as bad as it has been thought to be... In fact it can be said that the possibilities of human nature have customarily been sold short.

What we call human nature in actuality is human habit.

What we believe as human nature in actuality is human habit.

Human nature is, by definition, a talkative one, imprudent, indiscreet, gossipy, incapable of closing its mouth and keeping it closed.

There you are; human nature in action, wrongdoers, blaming everybody but themselves. We are all like that.

Human's intrinsic nature manifest in it's misunderstandings

There is not one human nature. There is not some uniform and unchanging way that everybody is and how everybody sees the world. Human nature has different meanings in different times and for different classes and groups in society.

So we know that human nature, and that includes our nature, yours and mine, can very easily turn people into quite efficient torturers and mass-murderers and slave-drivers...To the extent that the statement is true, and there is such an extent, it's just not relevant: human nature also has the capacity to lead to selflessness, and cooperation, and sacrifice, and support, and solidarity, and tremendous courage, and lots of other things too.

Mutability of temper and inconsistency with ourselves is the greatest weakness of human nature.

I do not think poor human nature so sorry a piece of workmanship as they would make it out to be; and as far as I have observed, I am fully satisfied that man, if left to himself, would about as readily go right as wrong. It is only this eternally sounding in his ears that it is his duty to go right which makes him go the very reverse.